Contact arrangement for vacuum switches

Abstract

A contact arrangement comprising two cup-type contacts having hollow-cylindrical contact carriers arranged coaxially with each other and having slots inclined in the same sense to the longitudinal axis of the contact arrangement. The slots act as a coil for generating a magnetic field for minimizing arc currents. The condition ##EQU1## is met in a range of the outside diameter D of the contact carriers of from 60 to 150 mm, a predetermined height H T of the contact carriers, a number s of the slots and an azimuth B of the slots. With this design, a contact arrangement with an axial magnetic field of at least 3.5 uT/A is obtained.

What is claimed is: 
     
       1. A contact arrangement for a vacuum switch comprising a pair of cup-type contacts, each contact comprising a hollow cylindrical contact carrier for supporting a contact plate having a cup depth H T , the contacts being arranged coaxially opposite each other and being movable in their axial direction relative to each other, the contact carriers each having a plurality of slots inclined in the same sense with respect to a longitudinal axis of the arrangement, the contact carriers having an outside diameter D, a range for the outside diameter D being 60 mm≦D ≦150 mm, and wherein the cup depth H T , the number of slots s and the azimuth B of the slots are determined by the following conditions: ##EQU5## 
     
     
       2. The contact arrangement recited in claim 1, wherein 0.15 D≦H T  ≦0.3 D. 
     
     
       3. The contact arrangement recited in claim 1, wherein the slots have an angle of inclination α E  in a cross-sectional plane with respect to the longitudinal axis and a distance b between a sectional line defining an end of a slot and a line drawn through the longitudinal axis, and wherein the following condition is met: ##EQU6## 
     
     
       4. The contact arrangement recited in claim 1 wherein the wall thickness W of the contact carrier is 7 mm W≦10 mm.